Withdrawal from chronic treatment with (+/-)-DOI causes super-sensitivity to 5-HT2 receptor-induced head-twitch behaviour in mice.
Mice were injected once daily for 13 days with (+/-)-DOI ((+-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane) and the induced head-twitch response (HTR) was scored. On days 2-5 HTR was reduced to less than 50% of day 1, and then returned to control levels by day 13. Challenge doses of (+/-)-DOI administered on days 15, 17 or 19 elicited significantly exaggerated responses. Thus, chronic treatment with (+/-)-DOI may cause an initial down-regulation followed by an up-regulation of 5-HT2 receptor function after cessation of such treatment.
Darmani
N A
NA
Department of Pharmacology/Toxicology, Virginia Commonwealth University/Medical College of Virginia, Richmond 23289.
Martin
B R
BR
Glennon
R A
RA
D000662:Amphetamines / Q000009:adverse effects*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D011985:Receptors, Serotonin / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000009:adverse effects*; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology*; D013997:Time Factors
D000662:Amphetamines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine